Bono surprised attendees at the Sarajevo Film Festival in Bosnia with an a cappella rendition of Bob Marley‘s ‘Redemption Song’ – watch the moment below.The frontman and The Edge were present at the film festival for a special screening of U2‘s Kiss The Future documentary when the legendary Irish vocalist hopped on the mic to serenade the crowd.Fans quickly joined in to sing along to the track after Bono unexpected belted out the opening lines to the Bob Marley classic. Watch a clip of the performance below.#Bono & #TheEdge at the #SarajevoFilmFestival for #KissTheFuture: "Redemption Song"Video © @28th_sff"When Bono's voice meets the silver screen.